I've dealt with them once in a while. They actually have quite broad powers, since the people they are chasing are technically in the custody of the bondsman.
"Taylor v. Taintor. Under Taylor v. Taintor, bounty hunters have (a) the right to seize fugitives without a warrant at any time of the day or night at the fugitive’s home; (b) the right, if necessary, to break and enter the fugitive’s house and to use whatever force is necessary to obtain custody of the defendant. They do not have to “knock and announce” before breaking down doors to search for the principal. Many courts extend this right to third-party residences. Bounty hunters also have (c) the right to “imprison” defendants until bounty hunters complete the final stage of their assignment—surrendering their prisoner to the sheriff of the county in which the fugitive was originally charged and admitted to bail; (d) the right to whisk captured fugitives across state lines back to the jurisdiction from which they fled, without seeking formal extradition or satisfying any procedural safeguards; and (e) the right to recover fugitives without “new process” (a new, separate warrant specifically authorizing them to make interstate seizures or forcible entries, searches, and arrests in the fugitive’s home)." - from the American Bar Association
That said, I don't have much good to say about them. The job seems to attract guys who wanted to be cops but couldn't pass the background.
