Since the unsatisfactory termination of the "Wakarusa war," certain leaders of the conspiracy had never given up their project of punishing the town of Lawrence. A propitious moment for carrying it out seemed now to have arrived. The free-State officers and leaders were, thanks to Judge Lecompte's doctrine of constructive treason, under indictment, arrest, or in flight; the settlers were busy with their spring crops; while the pro-slavery guerrillas, freshly arrived and full of zeal, were eager for service and distinction. The former campaign against the town had failed for want of justification; they now sought a pretext which would not shame their assumed character as defenders of law and order. In the shooting of Sheriff Jones in Lawrence, and in the refusal of ex-Governor Beeder to allow the deputy-marshal to arrest him, they discovered grave offenses against the territorial and United States laws. Determined also no longer to trust Governor Shannon, lest he might again make peace, United States Marshal Donaldson issued a proclamation on his own responsibility, on May 11, 1856, commanding "law-abiding citizens of the Territory" "to be and appear at Lecompton, as soon as practicable and in numbers sufficient for the proper execution of the law." Moving with the promptness and celerity of preconcerted plans, ex-Vice-President Atchison, with his Platte County Rifles and two brass cannon, the Kickapoo Rangers from Leavenworth and Weston, Wilkes, Titus, Buford, and all the rest of the free lances in the Territory, began to concentrate against Lawrence, giving the marshal in a very few days a "posse" of from 500 to 800 men, armed for the greater part with United States muskets, some stolen from the Liberty arsenal on their former raid, others distributed to them as Kansas militia by the territorial officers. The Governor refused to interfere to protect the threatened town, though an urgent appeal to do so was made to him by its citizens, who after stormy and divided councils resolved on a policy of non-resistance. [Sidenote: Memorial, Senate Ex. Doc., 3d Sess. 34th Cong. Vol. II., p. 77.] They next made application to the marshal, who tauntingly replied that he could not rely on their pledges, and must take the liberty to execute his process in his own time and manner. The help of Colonel Sumner, commanding the United States troops, was finally invoked, but his instructions only permitted him to act at the call of the Governor or marshal. [Footnote: Sumner to Shannon, May 12, 1856. Senate Ex. Doc., No. 10, 3d Sess. 34th Cong. Vol. V., p. 7.] Private persons who had leased the Free-State Hotel vainly besought the various authorities to prevent the destruction of their property. Ten days were consumed in these negotiations; but the spirit of vengeance refused to yield. When the citizens of Lawrence rose on the 21st of May they beheld their town invested by a formidable military force.