diff --git a/pandas/core/arrays/_mixins.py b/pandas/core/arrays/_mixins.py
index 95a003efbe1d0..948ffdc1f7c01 100644
--- a/pandas/core/arrays/_mixins.py
+++ b/pandas/core/arrays/_mixins.py
@@ -180,13 +180,10 @@ def _validate_shift_value(self, fill_value):
         return self._validate_fill_value(fill_value)
 
     def __setitem__(self, key, value):
-        key = self._validate_setitem_key(key)
+        key = check_array_indexer(self, key)
         value = self._validate_setitem_value(value)
         self._ndarray[key] = value
 
-    def _validate_setitem_key(self, key):
-        return check_array_indexer(self, key)
-
     def _validate_setitem_value(self, value):
         return value
 
@@ -198,7 +195,8 @@ def __getitem__(self, key):
                 return self._box_func(result)
             return self._from_backing_data(result)
 
-        key = self._validate_getitem_key(key)
+        key = extract_array(key, extract_numpy=True)
+        key = check_array_indexer(self, key)
         result = self._ndarray[key]
         if lib.is_scalar(result):
             return self._box_func(result)
@@ -206,10 +204,6 @@ def __getitem__(self, key):
         result = self._from_backing_data(result)
         return result
 
-    def _validate_getitem_key(self, key):
-        key = extract_array(key, extract_numpy=True)
-        return check_array_indexer(self, key)
-
     @doc(ExtensionArray.fillna)
     def fillna(self: _T, value=None, method=None, limit=None) -> _T:
         value, method = validate_fillna_kwargs(value, method)
diff --git a/pandas/core/arrays/datetimelike.py b/pandas/core/arrays/datetimelike.py
index eb5e5b03fe243..f1455aa864197 100644
--- a/pandas/core/arrays/datetimelike.py
+++ b/pandas/core/arrays/datetimelike.py
@@ -65,7 +65,7 @@
 from pandas.core.arrays._mixins import NDArrayBackedExtensionArray
 import pandas.core.common as com
 from pandas.core.construction import array, extract_array
-from pandas.core.indexers import check_setitem_lengths
+from pandas.core.indexers import check_array_indexer, check_setitem_lengths
 from pandas.core.ops.common import unpack_zerodim_and_defer
 from pandas.core.ops.invalid import invalid_comparison, make_invalid_op
 
@@ -294,7 +294,7 @@ def _get_getitem_freq(self, key):
         elif self.ndim != 1:
             freq = None
         else:
-            key = self._validate_getitem_key(key)  # maybe ndarray[bool] -> slice
+            key = check_array_indexer(self, key)  # maybe ndarray[bool] -> slice
             freq = None
             if isinstance(key, slice):
                 if self.freq is not None and key.step is not None: