Short answer. No separate warrant is needed. Rule 126, Section 13 provides that a person lawfully arrested may be searched for dangerous weapons, or for anything that may have been used or that constitutes proof of the offense, without a search warrant. The lawfulness of the arrest itself is what justifies the search.
What the law says
A person lawfully arrested may be searched for dangerous weapons or anything which may have been used or constitute proof in the commission of an offense without a search warrant.
Rule 126, Section 13 — Search incident to lawful arrest. Read the full provision →
The arrest must be lawful for the exception to apply
Section 13's exception is expressly tied to a person 'lawfully arrested.' The search-incident-to-arrest exception does not stand on its own — it borrows its legitimacy from the arrest being lawful in the first place. An unlawful arrest does not carry this warrantless search authority along with it. If the arrest itself is later found invalid, evidence obtained through a search conducted under this exception can also become vulnerable to exclusion.
What the search may cover
The rule limits what can be searched for: dangerous weapons, or anything which may have been used or constitutes proof in the commission of the offense. This ties the scope of the search to officer safety and to evidence connected with the offense for which the arrest was made, rather than an unlimited search. Items entirely unconnected to officer safety or to proof of the offense for which the arrest was made fall outside what this particular exception reaches.
Why no warrant is required here
Ordinarily a search requires a warrant under the preceding sections of Rule 126, but Section 13 recognizes that requiring officers to obtain a warrant after a lawful arrest, before securing weapons or evidence connected to that arrest, would be impractical and could endanger the officer or allow evidence to be lost. A warrant obtained afterward for unrelated evidence found this way is a separate matter this section does not itself resolve.
Why this exception does not become a general license to search
Because the exception is anchored to the arrest and to weapons or evidence connected with the offense, it does not authorize an officer to use a lawful arrest as a pretext for an open-ended search of a person's belongings or premises unrelated to the offense or to officer safety. Courts examining a search conducted under this exception look at whether the scope actually stayed within what the lawful arrest could justify, not simply whether an arrest happened to occur at some point.
Who this binds and the consequence of overreaching it
Section 13 binds the arresting officer to keep the search within its two justifications — officer safety and evidence of the offense for which the arrest was made — rather than treating the lawful arrest as blanket authority. An officer who searches beyond that scope, or who relies on an arrest that later turns out to be unlawful, risks having whatever was seized excluded from evidence, since the warrantless search's validity rises or falls with the lawfulness of the arrest and the connection of the search to its two permitted purposes.