Hines, J.
(After stating the foregoing facts.)
1. In the fifth ground of the amendment to his motion for new trial the defendant Buddie Wall asserts that the court erred in permitting W. D. Cunningham to testify as to the difficulty which took place on the morning preceding the night of the homicide between him and Fate Chapman, arising out of his effort as marshal of Byromville to collect, or enforce the collection of, a tax fi. fa. of that town against Chapman. In this difficulty Cunningham, while endeavoring as marshal to collect or levy said fi. fa. on the property of Chapman, became involved in a' tussle with *316Chapman, and during the same, shot the latter in one of his legs. One of the theories of the State in this case is that the defendant and some or all of his codefendants had, at the time of the killing of the deceased, assembled themselves together at the home of Chapman, had shot off their pistols for the purpose of attracting and' drawing the white people into ambush at Chapman’s house for the purpose of killing them, and that at the time of his homicide these defendants were assembled at the Chapman house to carry out this purpose. There is some evidence from which the jury might draw an inference that this contention was true. We do not mean to say that this contention is true. In view of this contention of the State, the evidence touching what had occurred the .previous morning between the marshal and Chapman was properly admitted for the purpose of showing the motive on the part of the defendants in arming themselves and meeting at the Chapman home that night. This evidence tended to show motive for the defendants to arm and meet at the Chapman house, and sheds light on the question whether they had formed a conspiracy to seek revenge for the injury inflicted by the marshal on Chapman. Evidence tending to show motive is always relevant and admissible. Wall v. State, 126 Ga. 86 (54 S. E. 815); Boone v. State, 145 Ga. 37 (88 S. E. 558).
2. We come next to consider the 6th, 8th, 9th, 10th, 11th, and 12th grounds of the amendment to defendant’s motion for new trial. In the sixth ground of his amendment the defendant claims that the court erred in permitting Ben Byrom to testify that on the afternoon before the deceased was killed he saw Lawyer West and told him that the police had shot Fate Chapman; and when asked why the police had shot him, he replied, about taxes. West said there ought to be something done about it. In the eighth ground it is alleged that the court erred in permitting Sam Byrom to testify that on the afternoon of the day on the night of which the deceased was killed he was passing the home of Bas Cobb, who said to this witness, that he expected he would need the witness that night about dark, and if he did he would let the witness know, and if the witness came he wanted the witness to bring his gun. In the ninth ground it is alleged that the court erred in permitting Sam Byrom to testify that as he came out of the door of Fate Chapman’s house' Jim Bennefield said, “You go, and.I will follow.” *317In the tenth ground it is alleged, that the court erred in permitting Sis Cobb to testify that she saw Lee Adams at her home on the day of the night before this homicide, that Adams was talking to her husband, Has Cobb, that he told her husband that he wanted her husband to come down there that night and be with them at Chapman’s, that he thought a crowd was coming in on them down there. In the eleventh ground it is complained that the court erred in permitting Martha Chapman to testify that she saw Chess Lewis at the home of Fate Chapman at the time of the difficulty between Chapman and the marshal, and that Lewis told Chapman if he were Chapman he would get a gun and shoot the son of a bitch, referring to the marshal. In the twelfth ground it is asserted that the court erred in permitting B. W. Espy to testify that he was in the hardware business at Montezuma, and that on the seventeenth day of May Luke West bought a box of 25 buckshot shells from him. The objection to the foregoing testimony was that the same was irrelevant, immaterial, and hearsay; and that such acts and declarations of other 'defendants, not in the presence of these defendants, and without their knowledge, was not admissible against them, in the absence of aliunde proof of conspiracy.
Unless a conspiracy is shown prima facie, evidence of the acts and declarations of one of the alleged conspirators can only operate against the person whose acts and declarations are proved, if he is on trial; or, if he is not on trial, they are not admissible against the defendants on trial, and should be rejected. Acts and declarations of a codefendant or alleged conspirator are admissible against the other only when made and clone during the pendency of the criminal enterprise and in furtherance of its object. Penal Code, § 1025; Foster v. Thrasher, 45 Ga. 517, 519; Horton v. State, 66 Ga. 690; Byrd v. State, 68 Ga. 661; Carter v. State, 106 Ga. 372 (5), 376 (32 S. E. 345, 71 Am. St. R. 262); Slaughter v. State, 113 Ga. 284 (38 S. E. 854, 84 Am. St. R. 242); Barrow v. State, 121 Ga. 187 (48 S. E. 950); Harrell v. State, 121 Ga. 607 (49 S. E. 703); Rawlins v. State, 124 Ga. 31 (12), 46 (52 S. E. 1); Coleman v. State, 141 Ga. 731 (82 S. E. 228); Smith v. State, 148 Ga. 332 (96 S. E. 632); Almand v. Thomas, 148 Ga. 369 (96 S. E. 962).
The declarations or conduct of one joint conspirator, made after *318the enterprise is ended, are inadmissible except against the person making them, and against others must be rejected as a narrative merely of past occurrences. Gibbs v. State, 144 Ga. 166 (86 S. E. 543); Almand v. Thomas, supra; Hicks v. State, 11 Ga. App. 265 (75 S. E. 12); Baker v. State, 17 Ga. App. 279 (86 S. E. 530).
This rule is subject to the qualification that each is responsible for the acts of the others only so far as such acts are naturally or necessarily done pursuant to or in furtherance of the conspiracy. Handley v. State, 115 Ga. 584 (41 S. E. 992).
The reason of this principle of law has been stated thus: “No man’s connection with a conspiracy can be legally established by what the others did in his absence and without his knowledge and concurrence.” U. S. v. Babcock, 3 Dill. (U. S.) 581, 24 Fed. Cas. 1913, No. 14487. The Supreme Court of California said: “ To admit such declarations — such hearsay testimony — in proof of the conspiracy itself would in civil matters 'put every man .at the mercy of rogues,’ . . and, in charges of criminal conspiracy, render the innocent the helpless victims of villainous schemes, supported and proved by the prearranged and manufactured evidence of the promoters thereof.” People v. Irwin, 77 Cal. 494 (20 Pac. 56). Again, it has been said: “A species or form of evidence which is in its nature inadmissible, unless some prior or other fact is proved, cannot be received to establish the fact, proof of which is an indispensable condition of its own admissibility.” Cuyler v. McCartney, 40 N. Y. 221, 33 Barb. 265.
The criminal conspiracy can not be shown by declarations of alleged conspirators, not in the presence of, and without the knowledge of, others sought to be bound thereby; but must be established by aliunde proof sufficient to establish prima facie the fact of conspiracy between the parties. Horton v. State, 66 Ga. 690, 693; Cuyler v. McCartney, supra.
Applying the above principles of law to the grounds of the motion for new trial now under consideration, the court erred in admitting the evidence set out in the 6th, 8th, 9th, 10th, and 12th grounds of the motion for new trial. The court did not err in admitting the evidence set out in the 11th ground. The defendants were tried jointly. The objection to the admission of this testimony was that it was irrelevant, immaterial, and hearsay. Clearly this evidence was admissible against Chess Lewis; and the *319defendant, Buddie Wall, should have objected specially to its admission as to himself and requested the court to instruct the jury that it was admitted solely to bind Chess Lewis, and not to bind Wall.
3. In the thirteenth ground it is complained that the court erred in permitting W. C. Kitchens to testify that on the night of the 17th of May he heard some shooting in the negro town across the railroad where Fate Chapman lived; that the negro lodge is down there next to Lee Adams’ house; that they are all there pretty close together; that there was just one volley after another, three, four, or five, from several shotguns and pistols; that there were fifty or a hundred shots, he reckons; that one Josey came after him and told him that the sheriff was down town and wanted him to come down there. The defendant objected to the introduction of this evidence, unless it was shown that the defendant was connected with this shooting. The court overruled this objection, and admitted the testimony. While it had not been shown, at the time this testimony was- delivered, that the defendant was connected with this shooting, this fact was afterwards proved by the State; and this cured any error in the prior admission of this evidence. McDaniel v. State, 103 Ga. 268 (3), 270 (30 S. E. 29); Harrell v. State, 121 Ga. 607 (3), 609 (49 S. E. 703).
4. In the fourteenth ground it is alleged that the court erred in refusing to permit Cossey Yinson, the sheriff of Dooly county,while on the stand, and during his cross-examination, to answer the following question propounded to him by counsel for the defendant : “ While these men were in jail we endeavored, Mr. Harvard and myself [meaning G. C. Bobinson, one of defendant’s-counsel] to get you to allow us to take one of these defendants out of the cell and have a conversation with him ? ” ' The solicitor-general objected to this question, on the ground that it was irrelevant and immaterial. Counsel for the defendant stated to the court that they expected to show that they requested the sheriff to allow them to take one of the defendants out,with a deputy to' another cell in the jail, away from the other parties, for a conference; and that the sheriff stated that he could not do that, that it would not be fair to the prosecution in the case, when the day before, or probably two or three days before, the prosecuting' attorney in the case went down to the jail, took several of these *320men out of the cells, talked with them, and some days thereafter went down to the jail, took some of the prisoners out of the jail • and off down to a house some distance from the jail and had a conversation with them. Counsel for the defendant further stated that they offered this testimony for the purpose of showing the interest of the sheriff in the case. The court sustained said objection and refused to permit the witness to answer the same. In this we think the court erred. We think that the defendant should have been allowed to prove any facts tending to show that the sheriff was a partisan of the State in this transaction. The state of a witness’s feelings toward the parties and his relation may always be proved for the consideration of the jury. Penal Code, § 1049. It was not error for the court to permit the State to prove by a witness for the defendant she was the latter’s paramour. Brown v. State, 119 Ga. 572 (3), 575 (46 S. E. 833); Lundy v. State, 144 Ga. 833 (88 S. E. 209). The jury may consider, in determining his credibility, the fact that a witness is the agent for the police in detecting crime. Clark v. State, 5 Ga. App. 605 (3) (63 S. E. 606). The fact that a witness is an employee of one of the parties is a proper matter to be considered by the jury in passing upon his credibility. Central of Ga. Ry. Co. v. Bagley, 121 Ga. 781 (49 S. E. 780). As a general rule a party may show any fact or circumstance that may affect the credit of an opposing witness. Bates v. State, 4 Ga. App. 486 (2), 491 (61 S. E. 888). Thus it may be shown that a witness is under obligation to the party calling him. 8 Enc. PI. & Pr. 120. So we think the court erred in refusing to permit the sheriff to answer the above question when propounded to him by counsel for the -defendant.
5. In the fifteenth ground error is assigned on the refusal of the court to rule out, on motion of the defendant, certain testimony of Sam Byrom, a witness for the State, to the effect that on the night of May 17 he saw a certain automatic pistol presented to him, and that Jim Bennefield brought it to his home. The defendant moved to rule out this testimony, on the ground that acts of Jim Bennefield, after the criminal enterprise, if any, was over, were inadmissible to bind the defendant. We do not think that acts of Jim Bennefield (even if he were a coconspirator of the defendant), done after the conspiracy, if any, had ended, were competent evidence for the State against the defendant on the trial of *321the latter; and that the court erred in not ruling out this testimony.
6. In the sixteenth ground it is asserted that the court erred in admitting in evidence certain pistols, guns, rifles, and ammunition, which had been identified by the sheriff. The objections to the admission of these weapons are that they were immaterial, that no one had sworn that they were at the scene of the killing, and that no prima facie case of conspiracy had been made out connecting the defendant with the alleged crime. These objections were specifically urged as to the gun'of Lawyer West, the gun found between the mattresses of Fate Chapman, and to the pistol of Jim Bennefield. We think these objections were not well taken as to any one of these weapons, except the pistol of Jim Bennefield, which we do not think had been shown to be his pistol except by his own act after the termination of the alleged unlawful enterprise.
7. In the seventeenth ground it is asserted that the court erred in charging the jury as follows: “ The words ‘ reasonable doubt,’ gentlemen, in their intendment and import, mean what they necessarily imply. They do not mean an entire absence of doubt, no doubt at all, an entire want of doubt, nor do they mean a whimsical, capricious, or fictitious doubt, but, as the words imply, a reasonable doubt.” The error alleged is that the charge does not explain what a reasonable doubt is, but only explains what a reasonable doubt is not. We do not find any error in this charge.
8. In the eighteenth ground the defendant complains that the court'erred in charging the jury'as follows: “It is only when a felony is intended that a killing is justifiable. A felony is an offense punishable by death or imprisonment in the penitentiary. If the assailant intends to commit a trespass only, to kill him is manslaughter. If he intends a felonjr, the killing is self-defense and is justifiable.” From the facts set out in this ground we can not say that the court erred in this instruction. It is not alleged why this charge was erroneous. Applicable to the law of self-defense, it was a correct statement of the law; but it would be improper for the court to give this instruction immediately after the court had read to the jury section 70 of the Penal Code, which gives the right to kill “any persons who manifestly intend and endeavor, in a riotous and tumultuous manner, to enter the liabi*322tation of another for the purpose of assaulting or offering personal violence to any person dwelling or being therein,” without making it plain to the jury that such instruction did not apply to this latter defense. Hudgins v. State, 2 Ga. 173, 182; Smith v. State, 106 Ga. 681 (32 S. E. 851, 71 Am. St. R. 286); McCrary v. State, 134 Ga. 416 (11), 428 (68 S. E. 62, 20 Ann. Cas. 101).
9. The court did not err in giving to the jury the instructions upon the subject of conspiracy, which are set out in the nineteenth, twentieth, and twenty-first grounds of the amendment to the motion for new trial, there being evidence from which the jury might infer the existence of a conspiracy.
10. We come to consider the twenty-second ground of the amendment to the motion for new trial in this case. The court was timely requested to charge, in effect, that no officer, including the sheriff, has any legal authority, without a warrant, to arrest a person charged with a crime, unless such offense was committed in his presence, or the offender is endeavoring to escape, or for other cause there is likely to be a failure of justice for want of an officer to issue a warrant. The court declined to give in charge to the jury the instruction embraced in this request. The court charged the jury on this subject as follows: “ It is further charged and contended on the part of the State, that the sheriff gathered together what is known as a posse, alleging that those he gathered together with him were acting under his deputization, and became officers together with and associated with the sheriff. In this connection I charge you that an arrest may be made for a crime by an officer, either under warrant, or without a warrant if the offense is committed in his presence, or the offender is endeavoring to escape, or for other cause there is likely to be a failure of justice for want of an officer to issue a warrant.” The above extract from the charge of the court embraces all the instructions of the court upon the subject of illegal arrest. The court did not mention the right of the defendants to resist an illegal arrest, and did not define the bounds in which they could act in so doing. In view of this situation the court committed error in refusing to give the principle of law embraced in the written request set out in this ground of the motion for new trial; and for this reason a new trial should be granted.
11. In the twenty-third ground of his motion the defendant *323complains of the refusal of the court, when properly requested in writing, to charge the jury that the sheriff and his alleged posse were without legal authority to attempt to enter the home and habitation of Fate Chapman in the manner in which they did. This request was too general and indefinite. Smith v. State, 125 Ga. 300 (54 S. E. 124); Spence v. Morrow, 128 Ga. 722 (58 S. E. 356); McElwaney v. MacDiarmid, 131 Ga. 97 (62 S. E. 20). Besides, an instruction which does not state any legal.proposition is properly refused. Wright v. Western etc. R. Co., 139 Ga. 343 (77 S. E. 161).
12. It is well settled that a person can use necessary force in resisting an illegal arrest. Such force must be proportionate to that used by the arresting officer. No person can justifiably kill another merely because such person is undertaking to illegally arrest the slayer. If, however, a person kill another to avoid an illegal arrest, and not in a spirit of revenge, the homicide is generally manslaughter, and not murder. If in the progress of the arrest the officer, or other person who attempts to make the same, manifestly intends or endeavors, by violence or surprise, to take the life of, or to commit a felony upon, the person sought to be arrested, then such person would be fully justified in taking the life of such officer nr person attempting his illegal arrest. If the circumstances surrounding the person at the time his illegal arrest is attempted are such as to excite the fears of a reasonable man that his life is in danger, or that a felony is about to be committed upon his person, and if under the influence of such fears, and not in a spirit of revenge, he slays the person or officer attempting to illegally arrest him, he would likewise be justifiable in slaying such officer or such person. If he were put in fear of a lesser injury than that of a felony, the homicide would be manslaughter. Thomas v. State, 91 Ga. 204 (18 S. E. 305); Franklin v. Amerson, 118 Ga. 860 (45 S. E. 698); Porter v. State, 124 Ga. 297 (52 S. E. 283, 2 L. R. A. (N. S.) 730); Perdue v. State, 135 Ga. 277, 284 (69 S. E. 184).
13. As a new trial is granted in this case, this court will not consider the question of the sufficiency of the evidence to authorize a conviction. Besides, on another trial, the. evidence may be different. Chess Lewis was jointly tried with Wall, but brought *324his case'to'this court in a separate writ of error assigning practically the same errors. His case is controlled by this case.
Judgment reversed.
All the Justices concur, except